Buttonhole-sewing machine.



11. ARENDT. BUTTONHOLE SEWING. MACHINE.

APPLICATION FILED JULY 10,1913.

' Patented Dec. 30, 1913.

i izh as: es 2 2 a i TwaZl'mkom itmcy omwem:

resents.

'* srA-rns nunonrn'nminnr, or meennnuns, GERMANY, nssrenen. .10 '11; MIINDLOS .& 09., or I nenmaune, sums/[Airgun rma. I a

iApplination mainl 10,

Be atrdrnorwm iI, Zttnnonrn a' subject the of iPrussia,mes1d 1ng:at 'M'agdelanng, iin Kingdom of Prussia and German Empire, have invented certain new.

i and mm improvements and Relating to;

following ism. spemfication. a

Machines, of the ing machines "of the in which the side or edge stitches and end or barring stitches any operation on the pa are formed alternately an automatioman-j ner, that'is-to say, without the :necesslty of j (If :operator for changing the .mechani erm edge 2 stitchestoJend stitches and-m "verse. 1' In button hole .sewingxnachines hitherto lmown mechanisms are employed fonautomatically' changing from the edge to the-endstitch formation and vice ve sa, which are extremely complicated and sensitive and therefore'unreliable and owing to their complicated" structure only reverse at the predetermined time when an exact coiiperatlon of the several reversing members is insured. In: the case of bu'tton hole sewing machines ,of the old kind running at high speeds required exact coiiperation of the parts is not always possible so that it frequently happens that the change from edge to end stitch for- -b mation or vice versa does not take place at the proper time, or fails altogether.

The object of my invention is .to avoid the complication of the reversing mechanism hitherto used and to employ in place thereof mechanisms which insure a positive reliable and automatic change from edge to end stitch formation and vice versa exactly at the predetermined time even in the-case of machines running at high speeds.

In accordancewith this invention the cam bar operating the needle-bar is acted upon by a cam-bargu'ide formed in the manner of the known stitch adjusting lever, and during the sewing of the'button hole this guide by means of a camplate or the like is at the redetermined times positively and automatically displaced in such a manner that a change fromedge to end stitch forma tion or vice versa takes place.

An'embodiment of the invention is diagrammatically illustrated by way of example on the accompanying drawing, wherein My" rinyentiun' zrelates ;to button hole sewnurronnorn snwm'e amen-inn.

" s same-non oflettersla'tent. 'Patmteflnmgfl, 1913,

' part at the machine withthe improved -st itch changing means and =F-igl2 a plan of the new device foroperafiingthe needle bar.

The button :hole sewingmachine comprises a trunk plate a mid an overhanging arm '12, end of which is formed as usually as n nasing for thereception and guidance of the vertical .needle die '0. The frame pf :theneedle bar participates together with the needle ibar d in a lateral displacement transverse to, -Ethe :feed direction nf-the material the-displacement being.

olotnined bymeans-ofanangle :lever e and a recipnocating rodf., Thefiisplacement of 1 the rod 7 is produced by a cam g mounted on lfl etop ofaQbevel pinion which is dri-ven by another bevelpinion from the main drivingshaft 72; of the machine. The needle bar d is actuated the cam rod 7, which is controlled by a cam bar "'de i havin the bar ii carrying-the neev shape of a bell-crank lever. This gui e i is 4 adapted to oscillate abbnt a .pivot is and is also piyotally connected by the Z with the said cam 'rodj. The guide Iai -is so arranged that-it, can be adjusted so as to per 'Init stitches of the desired size and length to bemade. According to the thus adjusted position of the cam rod guide; the rod f will e given a smalleror larger reciprocating movement andthereby will impart to the needle bar a greater or smaller lateral displacement transversely of the direction of feed of the material.

v The shifting of the cam rod guide for the purpose of changing from edge to end stitch formation is effected automatically and positively at the proper moment. In the eX- ample here illustrated this is obtained by .meansof cam projections m of the feed plate nforming'part of the feed mechanismi The nature of the connection of the lever acted upon'by the said cam projections with the cam rod guide may vary as desired. In'

the construction here illustrated a lever r rests by means of a roller-0 against the periphery of the feed plate. This lever is rigidly connected with a perpendicular shaft it. This shaft it carries a lever s having a slot which is positively connected by a connecting rod 6 with one arm of the lever 2'. The connecting rod t is rendered adjust-able in length in any convenient manner. Simi- Figure 1 is a. side elevation of the upper larly, the pointed connection between the connecting rod t and the slot s can be modified by appropriately "shifting the pin conthe cam g bymeans of which the cam rod f is given a lateral displacement which is converted into a, short reciprocating movement by the connection of the cam rod f with the cam rod guide 2'. According to the-position of the cam rod guide i'which is dependent upon the feed plate n, the reciprocating movement of the cam rod will be larger or smaller, and the change from edge stitch t0 end stitch formation will be automatic and take place when the roller a runs onto the cam curve m. The extent of the displacement of the cam rod guide can beregulated 2 within desired limits, by adjusting the position of the connecting pin for therod t in the slot in the part 8. i

What I- claim is: v

. In a buttonhole sewing machine, the combination with a 'needle bar, of means for changing the movement of said needle bar from movement to produce end stitch tomovement to produce edge stitch and vice versa; sanl means compnsmg a cam, a cam ;i-o 1;a bell crank lever, a link connecting the lever andieam rod, a feed plate having cam profe'ctions and arranged to rotate in unison with saidcam, an adwstable rod-connected "witlrthe bell crank lever, a slotted lever engaging said adjustable rod and adjustable relativeth'ereto, a second lever connected to the slotted lever'and having an end engaging said feed plate andmeans connecting the cam rod,with said needle bar.

In testimony whereof I have afiixed my signature in presence of two witnesses.

RUDOLPH ARENDT.

I Witnesses:

JOHANNES HEoHT, ,WILHELM LAUNN. 

